Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Most of us have microscopic, worm like mites named Demodex that live in our eyelashes and have claws and a mouth.
-137
The human brain has the capacity to store everything that you experience.
4k
When you take a step, you are using up to 200 muscles.
886